Sams Teach Yourself C++ in 21 Days

Advanced Inheritance 575

16

136: }

137: private:

138: PartNode * pHead;

139: int itsCount;

140: static PartsList GlobalPartsList;

141: };

142:

143: PartsList PartsList::GlobalPartsList;

144:

145: // Implementations for Lists...

146:

147: PartsList::PartsList():

148: pHead(0),

149: itsCount(0)

150: {}

151:

152: PartsList::~PartsList()

153: {

154: delete pHead;

155: }

156:

157: Part* PartsList::GetFirst() const

158: {

159: if (pHead)

160: return pHead->itsPart;

161: else

162: return NULL; // error catch here

163: }

164:

165: Part * PartsList::operator[](int offSet) const

166: {

167: PartNode* pNode = pHead;

168:

169: if (!pHead)

170: return NULL; // error catch here

171:

172: if (offSet > itsCount)

173: return NULL; // error

174:

175: for (int i=0;i<offSet; i++)

176: pNode = pNode->itsNext;

177:

178: return pNode->itsPart;

179: }

180:

181: Part* PartsList::Find(int & position, int PartNumber) const

182: {

183: PartNode * pNode = 0;

184: for (pNode = pHead, position = 0;

185: pNode!=NULL;

186: pNode = pNode->itsNext, position++)

187: {

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